/Engine/Source/Editor/SequencerCore/Public/MVVM/Extensions/IPinnableExtension.h
Default implementation forIPinnableExtension, with helper method to cache pinned states for children of a pinned branch
class FPinnableExtensionShim : public [UE::Sequencer::IPinnableExtension](API\Editor\SequencerCore\MVVM\Extensions\IPinnableExtension)